Offset contact alignment indicator



Oct. 30, 1951 3 E. A. ARP 2,573,531

OFFSET CONTACT ALIGNMENT INDICATOR Filed June a, 1947 2 SHEETSSHEET 1 INVE'NTOR EVVALD A.ARP BY )V-HQ AT TORNE Y Oct. 30, 1951 ARP OFFSET CONTACT ALIGNMENT INDICATOR 2 SHEETS SHEET 2 .Filed June 6, 194" w T N E v N EWALD A. ARP 5%. MW

AT TORNEY Patented Oct. 30, 1951 F ET O T CT A NMEN I D QAT Ewald A. Arp, Minneapolis, Minn., assignor to I bin Arp Manufacturing. Company, Mi ap l s, Minn" a corp ratio Qfv M nes-89m Application June 6,1947, erial No; 752,959

This invention relates to an indicating device adapted for use in the operation of relatively centering and alining a bearing'to be. bored or rebored and an appropriate tool for boring or reboring the bearing. Stated otherwise, the invention has relation to an indicating device which can be employed to readily and dependably check the accuracy with which a bearing to be bored and an appropriate tool for boring said bearing are relatively centered and alined.

The indicating device as herein illustrated and described has been devised to be especially useful in checking accuracy in the operation of centering and alining boring bars with crank shaft bearings and cam shaft bearings of internal combustion engines.

An object of the invention is to provide a novel and improved indicating device for checking the accuracy of the centered and alined'relation of a bearing to be bored or rebored and an appropriate tool for boring or reboring the bearing.

A further object is to provide an indicating device which will include mechanism of novel and improved construction for accurately checking the centered and alined relation of a bearing to be bored or rebored and an appropriate tool for boring or reboring the bearing.

And a, further object is to provide an indi: cating device, for use in the operation of relar tively centering and alining a bearing to be bored or rebored and an appropriate tool for boring or reboring the bearing, wherein will be incorporated desirable and improved features and characteris tics of construction novel both as individual entities of said indicating device and in combination.

With the above objects in-view, as well as others which will appear as the specification proceeds, the invention comprises the construction, ar

rangement and combinationof parts as now to be fully described and as hereinafter to be speci fical- 1y claimed, it being understood that the disclosure herein is merely illustrative and intended no Way in a limiting sense, changes in details of construction and arrangement of parts being permissible as long as within the spirit of the invention and the scope of the claims which follow.

In the accompanying drawing forming apart of this specification,

Fig. 1 is an elevational view, partially broken away, of a machine for boring engine bearings with an engine block situated in the ma hine as when being properly centered and alined with re; at n I? .-b.9 .e .ba supp t ;or ocating-unmet said machine, disclosing the. indicating device of theinvention as when applied to use;

Fig. 2 is an enlarged elevational View of said. indicating device also disclosing a fragment of aboring bar support or locating unit of the. machine of Fig. 1 in which theindicating device is mounted; 1

' Fig. 3 is an end elevational-view of said indicating device as it would appear from the left in Fig. 4;

Fig. l is an elevational View of the indicating device as it would appear from the-bottom of the sheet in Fig. 2

Fig. 5 is a central longitudinal sectionalview, taken substantially on line 5-5 in Fig. 4, disclosm a ball point of an actuator barfiof the indieatingdevice as when'cngaged against the inte'r'nal'surfaceof a bearing to be bored;

Fig. 6 is an enlarged transversesectional view, taken substantially on line 5-6 in Fig. 5';

' Fig. 7is anenlarged transverse sectional View, taken substantially on line 'l'i' inFig. 5; and

Fig. 8 is a fragmentary sectional View detailing parts, including an actuator gear, a clutchelement and a hollow cylindrical element, of'said' indicating device.

In Fig. 1 of the drawings, l5 denotes a machine for'bori'ng engine bearings, liire'presents'a'n engine block as when situated in said machine with one of" its crank shaft bearings I! being centered and 'alined with a boring bar support or locating unit 18 of the machine, 'and"l9*designates an indicating device made according to the inven-'- tion as 'when'applied to use to checktl'ie accuracy of the" relative centering and alining of said crank shaft bearing iland boring bar suppor' t or locating unit' [8 during the centering and alining operation. A mainframe of the machine l5 includes a supporting base 29 for a carriage or platform 2|, a standard 22 extending vertical-1y upwardly from said supporting base 253 at a side of said carriage or'p1atform'2'l and a horizontal arm 23 at 'the upper end of said standard 2.2 with which the boring'bar support or locating unit 18 is integral or rigid. .The'horizontalarm 23. is at .the'side of theestandardiz adjacent the supp'orthigbase .22 and said boring-barsupport o'r'locatingl unit 1.8 is directly above andin properly. spacedre'lation tothe carriage or platform 21. A usual finishedinternal cylindrical bearing surface of the boring bar support .or locating unit [.8 is dehoted lilis The machine |.5includes mechanism, forming no part of the present invention and not necessary to be .des'cribed,'Tfor accomplishing rotativead- 3 justment and anchoring of the engine block 16 and for accomplishing vertical and horizontal ad- Justment of the carriage or platform 2|, thus to accomplish vertical and horizontal alinement of the crank shaft bearing l1 and the boring bar support or locating unit l8. Of course, vertical and horizontal alinement of said crank shaft bearing and boring bar support or locating unit could be accomplished by manipulation of the boring bar support or locating unit relative to the engine block 16, or by relative manipulation of both said boring bar support or locating unit and said engine block. The indicating device herein illustrated and described is for checking the accuracy with which a bearing to be bored or rebored and an appropriate tool for boring or reboring said bearing are relatively centered and alined, not matter how the centering and alining operation is accomplished.

A body member 25 of the indicating device is constituted as an elongated hollow cylindrical; element open at both of its opposite ends -An end portion of said body member or hollow cylindrical element 25 bounds or defines a first chamher or concavity 26, an intermediate portion of the body member or hollow cylindrical element bounds or defines a second chamber or concavity 21, and the end portion of said body member or hollow cylindrical. element at the side of the second chamber or concavity 21 opposite the first chamber 1 or concavity 26 bounds or defines a third chamber" or concavity 28. The first and second chambers or concavities 25 and 21 are in alined, coaxial, contiguous relation, and the first chamber or concavity 26'has diameter and length somewhat greater than the diameter and length of the second chamber or concavity 21 in the disclosure as made. The second and third chambers or concavities 21 and 28 are in alined, co-

axial, spaced relation, the second chamber or of adjacent the third chamber or concavity 28,

also extending diametrically across the body member or hollow cylindrical element in parallel relation to the passageway. Said passageway 29 and said elongated rectilinear slot 39 are in a plane passed diametrically through all of thej first, second and third chambers or concavities 26, 21 and 28. An intermediate portion of the,

length of the elongated rectilinear slot 30, at the base of said elongated rectilinear slot, is open, as at 3|, to the adjacent end of the third chamber or concavity 28, and an intermediate portion of the length of said passageway 29 is open, as at 32, to the adjacent end of the second chamber or concavity 21. A transverse wall of the body member or hollow cylindrical element 25, in surrounding relation to the opening 32 and bounding. or defining the adjacent end of the second chamber or concavity 21, is indicated 33. A knurled surface of the end portion of the body member or hollow cylindrical element 25 having the first chamber or concavity 26 is denoted 81. 7

An inner end portion of a cylindrical shell or sleeve 34 of the indicating device is snugly fitted upon the end portion of the body member or hollow cylindrical element 25 bounding or defining the third chamber or concavity 28 with the inner end of said cylindrical shell or sleeve engaged against an annular flange 35 of said body member or hollow cylindrical element in surrounding relation to said third chamber or concavity and in adjacent relation to the passageway 29 and the elongated rectilinear slot 30. The shell or sleeve 34 includes a finished external cylindrical bearing surface 36, and a locking screw 31 retains saidshell or sleeve in fixed relationto the body member or hollow cylindrical element'25. Anj outer end portion of the shell or sleeve 34 projects outwardly beyond the outer end of the end portion of the body member or hollow cylindrical element 25 which bounds or defines'the third chamber or concavity 28. In

the disclosure as made, the outer end portion of said shell or sleeve, which projects outwardly from the body member or hollow cylindrical element 25 i somewhat longer than the inner end,

portion of the shell or sleeve which is snugly fitted upon said body member or hollow cylin drical element.

A head member 33 of the indicating device is constituted as an elongated hollow cylindrical entity 39 with head proper 49. The end portion of the hollow cylindrical entity 39 opposite the head proper 40 is snugly fitted into the outer end portion of the shell or sleeve 34 with the outer end of said shell or sleeve engaged against an annular shoulder 4| of said head member 38 in surrounding relation to said hollow cylindrical entity 39 and in adjacent relation to said head proper All The construction and arrangement are such that when the head member 38 is inserted in the shell or sleeve 34, the end of the elongated hollow cylindrical entity 39 spaced from or opposite the head proper 49 is situated in spaced relation to the adjacent end of the body member or hollow cylindrical element '25. locking screw for retaining the head member 38 i5: in'fi'xedrelation to said shell or sleeve 34 is represented 42. The outer end portion of the elongated hollow cylindrical entity 39, adjacent the head proper 40, includes alined, oppositely ,disposed, elongated slots 43,43 which extend longitudinally of said elongated hollow cylindrical entity and are open to an open-ended elongated slot 44 extending diametrically across said head proper. calibrations on an outer surface of the head proper 40, at a" side of the elongated slot ball point and said'compression coil spring, An

oblique annular flange '51 upon the correspondin end-of the actuator bar precludes possibility gf removal of said ball pointfrom said actuator ar. suitable to its intended purpose, and actuator bars such as 46 of different lengths can beselectively employed in a single indicating device.

actuator gear 52, pivotallymounted on" A ball point 48 at an end of The actuator bar 46 can be of any length assass n a cross pin 53 supported inthe body member or hollow cylindrical element and situated in the third chamber or concavity 28, lies in the plane of and is in mesh with the rack 41.

Ahollow cylindrical element 54 has a bifurcated end portion providing oppositely disposed extension pieces 55, 55 of said hollow cylindrical element rotatably mounted, as at 56, 56, on the cross pin 53 at opposite sides of the actuator gear 52. That is to say, said actuator gear 52 is situated between the extension pieces 55, 55 in spaced relation to the body portion of the hollow cylindrical element 54. The construction and arrangement will be such that said actuator gear 52 and said hollow cylindrical element 54 will be permanently situated at the midlength ofthe cross pin 53. The hollow cylindrical element 54 is supported on the cross pin 53 for swinging movement between spaced apart, oppositely disposed stop members 51, 51 in'the body member or hollow cylindrical element 25 at either side of said hollow cylindrical element 54 in spaced relation to the cross pin 53, adjacent the outer end of the third chamber or concavity 28, and the outer end portion of said hollow cylindrical element 54 is situated within the shell or sleeve 34 between the inner end of the body member or hollow cylindrical element 25 and the head member 38.

A clutching element for normally frictionally retaining the actuator gear 52 and the hollow cylindrical element 54 in fixed relation, is indicated 58. As disclosed, said clutching element 58 is constituted as a flat piece of fibrous material. A body portion of the clutching element is snugly situated in the space between the oppositely disposed extension pieces 55, 55 of the hollow cylindrical element 54 in alined relation with the actuator gear 52 in direction longitudinally; of the body member or hollow cylindrical element 25, an end of said clutching element at the side of its body portion adjacent the actuator gear includes spaced apart, obliquely disposed friction surfaces 59, 59 engaged against the teeth of said actuator gear, and a pointed end portion 6|! of the clutching element at the side of its body portion opposite the actuator gear is situated within the body portion of the hollow cylindrical element 54.

A pointer arm actuator 6|, situated in the end portion of said hollow cylindrical element 54 spaced from or opposite the cross pin 53, is an element of disc configuration in the disclosure as made. A side cut-out portion 62 of the actuator 6| is for a purpose to be made plain, and an oblique annular flange 63 upon the end of the hollow cylindrical element 54 adjacent the. actuator 6| is for retaining said actuator in said hollow cylindrical element.

A clutching element retainer 64, situated in an intermediate portion of the hollow cylindrical element 54, also is an element of disc configuration in the disclosed embodiment of the invention. A center cut-out portion 65 of the retainer 64' receives the pointed end portion 69 of the clutching element 58, and a compression coil The point of the end portion diverging side surfaces of said end portion at:

opposite sides of said point.

A pointer arm 61, rotatably mounted on a pivot pin BB'supported in the inner end portion of the elongated hollow cylindrical entity 39 in alined relation with the hollow cylindrical element 54 in direction longitudinally of the indicating device, includes a longer leg 69 thereof at the side of said pivot pin 68 opposite said hollow cylindrical element 54. and a shorter leg 19 thereof at the side of the pivot pin 68 adjacent the hollow cylindrical element. The longer leg 69 is in alinement with the elongated slots 43, 43 in the hollow cylindrical entity 39 and with the elongated slot 44 across the head proper 40 in direction transversely of the head member 38, and an offset portion 1| upon the outer end of said longer leg 69 is situated to be movable along the calibrations 45. The cutout portion 62 of the actuator Si is at the side of said actuator which is adjacent the ballpoint end of the actuator bar 46 and in alined relation with the shorter leg 16 of the pointer arm 61. The free end portion of said shorter leg 10 is situated in the side outout portion 62 and includes a knife edge 12 engaged against the adjacent edge of said actuator 6i. A coil spring 13, upon the pivot pin 68 and having one of its ends 14 attached to the longer arm 69 and its other end 15 attached to the head member 38, retains the knife edge 12 against the actutaor 6| and normally retains the hollow cylindrical element 54 against the stop member 51 at the side of said hollow cylindrical element opposite the ball point end of the acr tuator bar 46, and said coil spring 13 also normally situates the pointer arm 61 so that its offset portion 1| is positioned at the end of the elongated slot 54 at the side of the indicating device adjacent said ball point end of said actuator bar. See. Fig. 3.

In the disclosed embodiment of the invention, the actuator bar 46, the actuator gear 52, the hollow cylindrical element 54, the clutching element 58 and the pointer arm 61 all lie substantially in a single plane passed longitudinally and diametrically through the indicating device.

An actuator arm for theactuator bar 46 is denoted 16, and a supporting block for said actuator arm is represented 11.

The supporting block 11 is snugly, slidably mounted in the second chamber or concavity 21, and a compression coil spring 18, between said supporting block and the transverse wall 33, normally retains the supporting block in spaced relation to said transverse wall, engaged against a stop member 19 supported by the body member or hollow cylindrical element 25 and situated in a transverse slot 99 in the outer end of said supporting block. The stop member 19 permits the supporting block 11 to have movement longitudinally of the indicatin device and limits possibility of rotative movement of said supporting block.

The actuator arm 16 is situated in a longitudinally extending slot Bl of the supporting block 11 which is disposed in perpendicular relation to the transverse slot 36, and said actuator arm is rotatably mounted on a pivot pin 82 supported by and situated substantially at the midlength of said supporting block. The longitudinally extending slot 6! opens to both of the opposite ends of the supporting block 11, and the actuator arm 16 is in alinement with the actuator bar 46 and mounted for swinging movement in a' plane extending diametrically of thebody 7 membere-o'nc-hollowlcylindrical. element and, longitudinally of said actuatoiilban. zseid cilia; tor-arm 1.5 includesla: longerleg 83; thereof. at the side of said pivotpin: 82 @opposite; the, actuator ban 46 and; a shorter leg ,BAUthereQf at the side;

of the pivot pin: 82., adjacent said; actuator bar.

chamber or concavity-26; and: projects beyond the corresponding end; of the body memben or hole, low-cylindrical element 25, and the..-shorter'leg 84' includes a minted. end;portipn-;.8fixadaptedto V be: en'gagedgsrithirteethaiof a racksflfi rigid .with

the actuator bar; Nisand: situated diametrically opposite and in alined relation with the teeth of I T 1 l5 The: actuator bar. A6 can he forcibiy: slidman:

ua'liy along thepassageway; 29 in instances:when-,

said iactuaaer bar is conveniently accessible.

the rack Al;

The actuator. arm; 'l'fi. isjfori forcibly sliding. the actuator bar 46, along said passageway 2 9 in: in:

veniently accessible for manual manipulation, as.;when .the actuator bar is in asmall bearing and: an onerator cannot. readily and easily have accesstorit. The-manner. in. which the actuator arm: as can be manipulated. to .causethe, .actuae tor bar V4.9 .t o--;b.eslid-in the, passageway 29, to.-

ward the-ballpoint end -.of: said actuator.- .har. in

practical; use of then-indicating device, will be obviqiis; maid actuator-Harm lfi-isnadapted to be, grasped-and pushed inwardly, together. with th supporting ,block H as. a unit and against re ent action .of the .compressioncoilspring 18;,suntil the pointedg endportion 85 1s engaged betweenteeth; of. the rackzBfi-and thenswung 1 uponxthephtotypin; '82 asan axis to! cause the actuatoribar to, shemoved. longitudinally. Upon release of; the actuator armq'kfi, the compression coilusprm '18 ,oflcourse will react to cause the pointed end portion 85 to be removed from-:the

9 n direction away f om sa d. nte nalsuriw o said. r n shaftbearina and' he poi er r 5 is disclos d a ab h midlenet uof the calibrationsdfi, gar-substantially at the loca:

tion of sa d, c ib t gns; 45 enoted f I 9- n F -v 3. The compression coil spring!!!) is of reater stre n hee-o spr ng -1 a d. f. sufii:

1 20V stances when said. actiiatorcbar may not be Q0111 in i elb arinesurface 3.6.015 said shellor-sleeve surface of the crank shaft bearingnll, to-be bored ,or-rebored, and said indicating device is rotated, while the ball point 48 is engaged against said internal surface of ,said bearing, to .cause said hall point to, be moved circumferentially of the bearing.

For convenience, the ,offset portion ltof: the

pointer arm; 56?, normally maybe. at B,- as: in

Fig. 3 of the drawings, but the manner iof calibrating can'be as preferred.

A reading for the indicating device is to be obtained before the actuator barAS with ball point 48 is caused to be revolved. In the dis.-

closure as made, a reading can be obtained by sliding. saidactuator bar 56 along the passageway 29 toward the internal surface ,ofa hearing, such as theinternal surface lof the, crank sha tbear ng t e wi e or ebor o-. aus. a a l point .48 to b fenced a inst saidinternel sur a o saide qunsie pressure suflic en co lapse ihesmi ression ccilsprin direction-away. from said ball cient st h t ausefthe a tuator see -5M0,

e r tet dand, the, holl w cylindri al ele ent; 54 to be swung away from the stop member 5-! against whichsaid' hollow cylindrical element normally is engaged when said compression coil p n e9 r a ts, upon release of the actuator bar 45, after being collapsed by forcing vof the ball point. 48 against the internal surface of'a bearing to be bored or rebored. The reading of the indicating device 'willgremain the same as the reading obtained in the manner as set forth throughout complete revolution of the indicating deyice with actuator bar; 46 in the borng bar support o v lo at ng unit L8 and, relatiyeto the internal surface of the. crank shaft bearingv H, provided said boring bar support or locating limit and. said crank shaft bearing are accurately relatively. centered vand alined.

Statedotherwise, should the offset portion H of: the-pointer armlt'l: be at is for" example, o-fwthe calibrations lii at the commencement of rotational" movement of the indicating 'device, said offset portion will remain at It through} out complete revolution of said indicating device when, and only when the liming bar; support or locatingnnit and the crank shaft hearing are accurately-centered and alined. A

'Thecfiset portion H of said pointer arm; 51 willbetetained atfO of the calibrations 4:5, at all times when the actuator bar 45 his itslba'll point 48 are unrestricted, as in Figs} Icyreason of" the fact Zthat thfe coil spring i normallr w ch? i i q shimmer elem a4 a i th st p membe '51. a th id o th er in e i eopsqsitei e ba l m and i ai ac ator. ta "and theibs n o .tnis tto'i member dictates epositi 'n ,of saidoffs et portion 1-], forcible slidlng movement of the eqt i tc lber qwa ihe. n r d c the crank shaft bearing jjgthe actuatorrge'a 552' will be rotated indirection to use said hollow cylindrical element 54 to have tendency tofbe wa -awa .i i m th ai m n id O t i device, .but movernent of :said hollow .e ,me woip s nd iti n. i i tsideof themi e ngd Y i -;9 Y Q y 7 .be nre l sie by said stop me nberW with which the hollow icylindr t" qrmally is engagedi Instead, e az ltnin zmoyement. of..the.

5 t w l... el-semi@Zrelativetoithe fric- ,9 5210f: the, clutching element 58 BB t orcihle sliding movement of the etuato r ihalr Qwardy'the ,internal surface of vsaid r nkcsh f 'lloearing 1-1.1 And, te -engagement qiitbeghollowicylindrical eIementR-SILWith-thestop .member 51 at the ;side of theindicating device adjacent-the :ball point endof the actuator bar 45 dictates the extent, to which'thepointer-arm 61 can be moved away from In Fig. 3 the limit position to which the offset portion II can be moved away from 0 is designated 20. With forcible sliding movement of said actuator bar in direction awayfrom its ball point end after said-stop member 51 at said side of the indicating device adjacent said ball point end has been engaged by said hollow cylindrical element 54, there will be sliding turning movement of the teeth of the actuator gear 52 relative to the friction surfaces 59, 59 of the clutching element 58 in direction opposite that in which said actuator gear slides over said friction surfaces when the actuator bar is forcibly slid in direction toward its ball point end. Thus, the clutching element 58 constitutes means for precluding possible breakage of parts of the indicating device, as well as an instrumentality for frictionally retaining the actuator gear 52 and the hollow cylindrical element 54 in fixed relation during swinging movements of said hollow cylindrical element between the stop members 51, 51 in response to rotative movement of said actuator gear.

'It will be apparent from the drawings that a part of the ballpoint 48 projects from the corresponding end of the actuator bar 46. Evidently, the extent of collapsing of the compression coil spring 49 in response to sliding movement of the actuator bar 46 toward the internal surface of a bearing to be bored can be controlled by engagement of the end of said actuator bar 46' having the oblique annular flange 5| with said internal surface thus to accurately control the extent of return movement of said actuator bar when released.

What is claimed is:

1. In an indicating device, a body member including a hollow portion, an actuator bar supported for movement transversely of said body member, a rack rigid and alined with said actuator bar, a supporting block slidably mounted in said hollow portion adjacent said rack for movement toward and away from the rack, means normally resiliently urging said supporting block in direction away from said rack, a pivot pin rigid with said supporting block, and an actuator arm rotatably supported upon said pivot pin for swinging movement in the plane of transverse movement of said actuator bar and rack, said actuator arm including a shorter leg thereof at the side of the pivot pin and supporting block adjacent said rack adapted to be engaged between teeth of the rack and a longer leg thereof at the side of said pivot pin and supporting block opposite said rack adapted to be manually manipulated.

2. In an indicating device, a hollow member, a cross pin supported therein, an actuator gear rotatably mounted on said cross pin, means for causing said actuator gear to be rotated, a hollow element mounted for swinging movement relative to said cross pin and fixed against longitudinal movement, stop-means'for limiting the extent of swinging movement of said hollow element, a clutching element within said .hollow element, .and spring means within said hollow element urging said clutching element into frictionalengagement with teeth of said actuator gear, said clutching element connecting said hollow element and said actuator gear with each other for swinging movement of the hollow element between said stop members in response to rotational movement of the actuator gear.

, 3. In an indicating device, a hollow member, an actuator gear therein, means supporting said actuator gear for rotational movement, means for causing said actuator gear to be rotated, an element mounted for swinging movement relative to said actuator gear supporting means and fixed .against longitudinal movement, stop means for limiting the extent of swinging movement of said element, a clutching element, and spring means urging said clutching element into frictional engagement with teeth of said actuator gear, said clutching element connecting said element and said actuator gear with each other for swinging movement of the element toward and away from said stop means in response to rotational movement of the actuator gear.

4. In an indicating device, a hollow member, an actuator gear therein, means supporting said actuator gear for'rotational movement, means for causing said actuator gear to be rotated constituted as an actuator bar supported for slidable movement transversely of said hollow member, an element mounted for swinging movement relative to said actuator gear supporting means and fixed against longitudinal movement, stop means for limiting the extent of swinging movement of said element, a clutching element, and spring means urging said clutching element into frictional engagement with teeth of said actuator gear, said clutching element connecting said element and said actuator gear with each other for swinging movement of the element toward and away from said stop means in response to rotational movement of the actuator gear.

5.,In an indicating device, a hollow member, an actuator gear therein, means supporting said actuator gear for rotational movement, means for causing said actuator gear to be rotated constituted as an actuator bar supported for slidable movement transversely of said hollow member and including a rack engaging teeth of the actuator gear, an element mounted for swinging movement relative to said actuator gear supporting means and fixed against longitudinal movement, stop means for limiting the extent of swinging movement of said element, a clutching element, and spring means urging said clutching element into frictional engagement with said teeth of the actuator gear at .a side thereof opposite said actuator bar, said clutching element connecting said element and said actuator gear with each other for swinging movement of the element toward and away from said stop means in response to rotational movement of the actuator gear.

6. In an indicating device, a hollow member including a cylindrical portion, an actuator gear therein, means supporting said actuator gear for rotational movement, means for causing said actuator gear to be rotated constituted as an actuator bar supported for slidable movement transversely of and projecting beyond a side surface of .said hollow member, an element mounted for swinging movement relative to said actuator gear supporting means and fixed against longitudinalmovement, stop means for limiting the extent of swinging movement of said element, a clutching element-and spring means urging said clutching element into frictional engagement with teeth of said actuator gear, said clutching element connecting said element and said actuator gear with each other for swinging movement of the element toward and away from said'stop means in response to rotational movement of the actuator gear.

7. The combination as specified in claim 3,

a and a pivotally supported pointer arm pivotally connected to said element.

8. The combination as specified in claim 6, and a pivotally supported pointer arm pivotally connected to said element.

'9. The combination as specified in claim 4, a point contact member supported by said actuatorbar for movement longitudinally thereof,

and collapsible resilient means normally urging saidpoint contact member outwardly of an end of said actuator bar.

a 10. The combination as specified in claim 6, a point contact member supported by said actuator bar for movement longitudinally thereof, and collapsible resilient means normally urging said point contact member outwardly of an end of said actuator bar.

11. The combination as specified in claim 4,

- a point contact member supported by said actuator bar for movement longitudinally thereof,

. collapsible resilient means normally urging said point'contact'member outwardly of an end of said 'actuator bar, and a pivotally supported pointer arm pivotally connected to said element.

12. The combination as specified in claim 6,

a point contact member supported by said actuator bar for movement longitudinally thereof, collapsible resilient means normally urging said point contact member outwardly of an end of said actuator bar, and a pivotally supported pointer arm pivotally connected to said element.

13. In an indicating device, a hollow member, an actuator gear therein, means supporting said actuator gear for rotational movement, means for causing said actuator gear to be rotated coni stituted as an actuator bar supported for slidable ing element, spring means urging said clutching element into frictional engagement with teeth of said actuator gear, said clutching element connecting said element and said actuator gear with each other for swinging movement of the element between said first and second stop members in response to rotational movement of the actuator gear, and a resilient device having strength less than that of said collapsible resilient means normally retaining said element against said first stop member.

14. The combination as specified in claim 13, and a pivotally supported pointer arm, pivotally 7 connected to said element.

15. In an'indicating device, a hollow member, an actuator bar supported for movement transversely of said hollow member, a rack rigid with said actuator bar, a block slidably mounted in said hollow member for movement toward and away from said rack, means normally urging said block in direction away from said rack, an actuator arm, and means supporting said actuator arm upon said block for swinging movement in r the plane of movement of said actuator 1961. and.

12 rack, said actuator arm including a first leg to be engaged between teeth of said rack and a second leg to'be manually manipulated at a side of said block opposite the rack.

16. In an indicating device, a hollow member, an actuator gear therein, means supporting said actuator gear for rotational movement, means for causing said actuator gear to be rotated con stituted as an actuator bar supported for slidable movement transversely of said hollow member and including a first rack engaging teeth of the actuator gear, an elementmounte'd for swinging movement relative to said actuator gear supporting means and fixed against longitudinal movement, stop means for limiting the extent of swinging movement of saidelementga clutching element, spring means urging said clutching element into frictional engagement With said teeth of the actuator gear at a side thereof opposite said actuator bar, said clutching element connecting said element'and actuator gear with each other for swinging movement of the element toward and away from said stop means in response to rotational movement of the actuator 7 bar and first and second racks, said actuator arm including a first leg to be engaged between teeth of said second rack and a second leg to be manually manipulated ata side of said block opposite the second rack.

EWALD A. ARP.

I REFERENCES: CITED. r,

The following references are of record iii-the file of this patent:

UNITED STATES PATENTS j v v Date Number Name 820,303 .Hansen May 8, 1906 1,076,682 Lucas Oct. 28, 1913 1,129,289 Grant Feb. 23, 1915 1,160,630 MacKinnon Nov. 16, 1915 1,649,197 Senchak Nov. 15, 1927 1,695,453 Carpenter Dec. 18, 1928 1,723,529 Schwieterman Aug. 6, 1929 1,876,280 Dunn Sept. 6, 1932 2,099,930 Emery Nov. 20, 1937 2,121,848 Winters June 28, 1938 2,124,006 Parker July 19, 1938 2,124,014 Street July 19, 1938 2,129,311 Street Sept; 6, 1938 2,165,017 Sisson ,July 4, 1939 2,179,602 Smith Nov. 14, 1939 2,181,077 Street Nov. 21, 1939 2,189,631 Farmer Feb. 6, 1940 2,341,809 Pearson Feb. 15, 1944 2,357,836 McGreevy, Sept. 12, 1944 2,445,455 Rights et 1. 'Ju1 20, 1948 FOREIGN PATENTS Number Country Date 63,052 Germany June 27, 1892 115,057 Australia Apr. 23, 1942 708,168 France Apr. 27, 1931 875,477 France June. 22, 1942 

